1. Field of the Invention
This invention relates to an electronic apparatus, such as a disk drive suspension, comprising an electrical component, such as a microactuator.
2. Description of the Related Art
A hard disk drive (HDD) is used in an information processing apparatus, such as a personal computer. The HDD comprises a magnetic disk rotatable about a spindle, a carriage turnable about a pivot, etc. The carriage, which comprises an actuator arm, is configured to be turned transversely relative to tracks about the pivot by a positioning motor, such as a voice coil motor.
A suspension is mounted on the actuator arm. The suspension comprises a load beam and flexure superposed thereon. A slider, which constitutes a magnetic head, is mounted on a gimbal portion formed near the distal end of the flexure. The slider is provided with elements (transducers) for accessing data, that is, for reading or writing data.
In order to overcome the increase in the recording density of disks, the magnetic head needs to be more precisely positioned relative to the recording surface of each disk. To attain this, DSA suspensions, such as the ones disclosed in Jpn. Pat. Appln. KOKAI Publications Nos. 2001-307442 (Patent Document 1) and 2002-50140 (Patent Document 2), have been developed. One such DSA suspension combines a positioning motor (voice coil motor) and microactuator. DSA is an abbreviation of dual stage actuator.
The microactuator element comprises a piezoelectric element of, for example, lead zirconate titanate (PZT) or the like. An element accommodation portion is formed in an electrically conductive plate member that constitutes a part of the suspension. The microactuator element is located in the element accommodation portion. The microactuator element serves to move the distal end side of the suspension in a sway direction (or transversely relative to tracks) at high speed.
The piezoelectric element of the DSA suspension is plate-like. A first electrode is disposed on one thicknesswise surface of the piezoelectric element, and a second electrode on the other surface. The first electrode is electrically connected to the conductive plate member through a conductive resin, such as silver paste. The conductive resin comprises conductive filler particles, such as silver particles in a resin material.
The conductive resin is applied in an uncured state between the conductive plate member and microactuator element. This conductive resin is cured after the application. In some cases, however, electrical resistance between the conductive resin and conductive plate member cannot be reduced by simply applying and curing the conductive resin. When a continuity test is conducted in a hot humid atmosphere, in particular, the electrical resistance between the conductive resin and conductive plate member may increase, causing conduction failure between the conductive plate member and an electrical component (e.g., the microactuator element).
In order to improve electrical conduction between the conductive resin and conductive plate member, a proposal has been made to plate a part of the conductive plate member (on which the conductive resin is disposed) with gold. A gold plating (gold deposit) cannot be oxidized and can achieve good electrical conduction to the conductive resin. Since gold is an inert metal, however, its adhesion to the conductive resin is poor. Thus, the peel strength of the conductive resin may be reduced in gold-plated areas.